T&T: Digital Antennas

[Ed Bruette]

Larry,

Thoughts;
Antennas are usually a compromise, especially in a marine installation.  It
is rare that we are able to install the "best" antenna to get the job done.
As in your case, there are mounting and space constraints that influence the
acquisition process.  The 16' 544-SSW may look like it is electrically 24'
to the transmitter but there is no way to make up for the missing 8' when it
comes to the reception of weak signals.  The 16' antenna only has 2/3s the
capture area of the 24' antenna.  There is a trade off on the transmit side
too but it may not be as noticeable.  

The easiest way to get a feel for the difference between a 16' and 24'
antenna is to set up a test station that can rapidly change or switch
between the 2 antennas and conduct testing with a few distant stations.
Propagation at the time of the test may provide some false conclusions if
you do a small number of test transmissions.  This is the poor man's way to
try to get some meaningful info without having access to lab equipment
required to do a scientific comparison.  Manufacturer's claims are often
confusing and misleading.  

The bottom line is that with a good transceiver you will probably be able to
talk to any station you can hear with the 16' antenna.  The 24' antenna will
hear and therefore be able to talk to more stations.  If you intend to do
significant offshore cruising I'd go with the 24' antenna.

So, take your best shot at the compromise that fits your installation
constraints, budget and performance needs.


Ed, N7NVP
PT-38  "Makin' Do"
Poulsbo, WA
 

-----Original Message-----
On Behalf Of Larry N. Brown
Subject: T&T: Digital Antennas

Sometimes the way a question is phrased is the key to the answer you get. I
was looking at the Shakespeare 390 antenna an I couldn't find anyone who had
it at a reasonable price who could ship it at a reasonable price. Then I
discovered the DA 534-SSW at a "reasonable" price but the mounting specs
require a deck mount. I have no place on which to do this. So, now I'm
looking at the 544-SSW which, although it's 16' long is "electrically" 24. I
received one very good report from a listee and some followup thinking by
another offline.

Does anyone have any experience with the shorter antenna? Any thoughts? It
certainly be an easier, stronger installation.

Regards,

Larry and Teri